Compressor and air conditioner having the same

ABSTRACT

A scroll compressor uses fatty-acid ester oil for lubrication when a hydro-fluorocarbon (HFC) based-refrigerant is used, and uses fatty-acid mineral oil when a hydro-chlorofluorocarbon (HCFC)-based refrigerant is used. The driving motor is a synchronous reluctance motor with a rotor comprised of a plurality of flat plates. Each plate has a plurality of magnetic flux barriers that extend in both a circumferential direction and a radius direction. An insulation film formed of a crystalline plastic film is interposed between a coil and a stator of the motor, and the coil is formed of wire with an enamel coating layer. These features result in less deformation of the driving motor. In addition, losses due to slippage at the driving motor are lowered. Further, thermal loss due to emission of the rotor is decreased.

BACKGROUND

1. Field

The present invention relates to a compressor, and more particularly, toa compressor and an air conditioner having the same.

2. Background

In general, a compressor converts mechanical energy into compressiveenergy. Compressors may be categorized into a reciprocating type, ascroll type, a centrifugal type, a rotary type and a vane type. Thescroll compressor may include a driving motor which drives a compressionpart to compress fluid.

The driving motor may be, for example, an induction motor, which has asimple structure, low cost, and is easily handled. However, slippagebetween the stator and the rotor of a motor can degrade performance inan induction motor. Further, induction current can generate heat, whichlowers efficiency due to thermal losses.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be described in detail with reference to thefollowing drawings in which like reference numerals refer to likeelements, and wherein:

FIG. 1 is a cross-sectional view of a compressor;

FIG. 2 is a cross-sectional view of a synchronous reluctance motor whichmay be applied to the compressor of FIG. 1;

FIG. 3 is a cross-sectional view of a stator of a synchronous reluctancemotor which may be applied to the compressor of FIG. 1;

FIGS. 4 to 6 are plan views of a rotor of a driving motor which may beapplied to the exemplary compressor of FIG. 1;

FIG. 7 is a schematic view of a compressor;

FIG. 8 is a sectional view of an alternative embodiment of a compressor;

FIG. 9 shows a refrigerator incorporating the compressor shown in FIG.1;

FIG. 10 shows an air conditioner incorporating the compressor shown inFIG. 1; and

FIG. 11 shows another air conditioner incorporating the compressor shownin FIG. 1.

DETAILED DESCRIPTION

Reference will now be made in detail to preferred embodiments, examplesof which are illustrated in the accompanying drawings.

A compressor and components thereof in accordance with embodiments asbroadly described herein are shown in FIGS. 1 to 7. Although a scrollcompressor is used for ease of discussion, it is well understood that amotor as embodied and broadly described herein may be applied to othertypes of compressors and/or used in other applications. That said, someof the features described below are specific to scroll compressors. Thefact that some features are specific to scroll compressors does not meanthat the other aspects of the disclosed and claimed compressors, anddriving motors, could not be applied to other types of compressors.Thus, the scope of the claims of this application are not to be limitedto scroll compressors, except where the claims are specifically directedto scroll compressor features.

Some compressors have used a chlorofluorocarbon (CFC)-based refrigerantsuch as CFC 11, CFC 12, CFC 113, CFC 114 and CFC 115. However, the useof these CFC-based refrigerants has been restricted worldwide, and thusHFC-based refrigerants, such as, for example, CFC 134a(1,1,1-tetrafluoroethane, CH2FCF3) has replaced many of the earlierCFC-based refrigerants. However, since HFC-based refrigerants havedifferent chemical structure, they are not as easily mixed withlubrication fluids, such as, for example, oil. In addition, they mayhave inferior abrasion resistance. Accordingly, when an HFC-basedrefrigerant is used in a compressor, performance of the compressor istypically degraded.

The exemplary compressor shown in FIG. 1 includes a hermetic casing 10to which a refrigerant suction pipe (SP) and a refrigerant dischargepipe (DP) are connected. A driving motor 20 is disposed at a lowerportion of the casing 10, and a compression device 30 is disposed at anupper portion of the casing 10.

The casing 20 includes a body 11 having a substantially cylindricalshape. The driving motor 20 and the compression device 30 are providedat lower and upper portions of the casing, respectively. An upper cap 12and a lower cap 13 cover upper and lower ends of the body 11. The body11 is formed with a cylindrical shape, and the upper and lower ends havesubstantially the same diameter. However, when an outer diameter (D1) ofthe driving motor 20 is larger than an outer diameter of the compressiondevice 30 (in this embodiment, an outer diameter of a plate portion of afixed scroll), a stepped portion may be formed between the driving motor20 and the compression device 30.

As shown in FIGS. 1 and 2, the driving motor 20 includes a stator fixedto an inner portion of the casing 10 which receives power from anexternal source. A rotor 22 is disposed inside the stator 21 with a gaptherebetween. A rotation shaft 23 is coupled to the rotor 22 so as totransmit a rotational force from the driving motor to the compressiondevice 30. The rotation shaft 23 may be coupled to the rotor 22 bypressfit, shrinkage fit, or other coupling methods, as appropriate.

The stator 21 includes a stator laminator 25 which has a cylindricalshape so as to rotatably position the rotor 22 at the center thereof. Acoil 26 is wound on the stator laminator 25 and connected to an externalpower source. The stator laminator 25 may form a ring-shaped magneticpath with a plurality of protruding poles 25 a extending from an innercircumferential surface of the magnetic path. As shown in FIG. 7, thestator laminator 25 is formed so that an outer diameter thereof. D1 canbe larger than its height H2 in a shaft direction. A radius r1 of thestator can be smaller than an outer diameter D2 of the rotor 22. Also,the stator laminator 25 is formed so that the outer diameter thereof. D1can be larger than an outer diameter D3 of the outermost compressionchamber between a fixed scroll 31 and an orbiting scroll 32. In certainembodiments, a height difference between a center of a rotor laminator27 in a shaft direction and a center of the stator laminator 25 in ashaft direction is within the range of 2˜3 mm, thereby preventingphysical interference between the stator 21 and the rotor 22 due to aneccentric load on the rotation shaft 23.

The stator laminator 25 may include a rotor insertion hole 25 b having asubstantially circular shape at its center. A plurality of protrudingfixing portions 25 c and cut-passages 25 d are alternately formed alongan outer circumferential surface of the stator laminator 25 so as toform a gas passage F with the casing 10.

As shown in FIG. 3, the protruding fixing portions 25 c and thecut-passages 25 d may be symmetrical with each other with the sameinterval therebetween. For example, a circumferential length between theprotruding fixing portions 25 c may be equal to a circumferential lengthbetween the cut-passages 25 d so as to minimize any deformation of thestator laminator 25.

A ratio (d1/w1) between a diameter (d1) of the rotor insertion hole 25 band a width (w1) of the stator laminator 25 may be greater than or equalto 2.1. Additionally, an angle θ formed between both ends of theprotruding fixing portion 25 c and a center of the stator 21 may be15°˜35°. In certain embodiments, at least two cut-passages 25 d areformed so that a ratio (QA₀/QA₁) between a sum (QA₀) of acircumferential length of each cut-passage 25 d and a sum (QA₁) of acircumferential length of each protruding fixing portion 25 c is0.2˜0.8.

The coil 26 may be successively wound on each of the protruding poles 25a of the stator laminator 25. The coil 26 may be implemented with acopper wire having an enamel coating layer with a separation transitiontemperature of more than approximately 120° C. formed on an outercircumferential surface of the copper wire. An insulation film formed ofa crystalline plastic film having a separation transition temperature ofmore than approximately 50° C. may be interposed between an outercircumferential surface of the coil and an inner circumferential surfaceof the stator laminator 25 contacting the coil. The coil 26 is formed soas to have a height H1 corresponding to 1.5˜3 times of the height H2 ofthe stator laminator 25.

The rotor 22 includes a rotor laminator 27. In certain embodiments, therotor laminator 27 may be formed from a plurality of thin steel plateslaminated in a shaft direction with an upper end plate 28A and a lowerend plate 28B disposed at upper and lower ends of the rotor laminator27, respectively.

In the embodiment shown in FIG. 4, each steel plate may be provided witha plurality of magnetic flux barriers 27 a formed in a circumferentialdirection and a radius direction, each plate having a substantiallycircular shape. In this embodiment, a distance (t1) from an outercircumferential surface of the steel plate to ends of the magnetic fluxbarriers 27 a is uniform. A width (t2) of the magnetic flux barrier 27 ain the radius direction, and a distance (t3) between adjacent magneticflux barriers 27 a in the radius direction each increase towards thecenter of the steel plate.

As shown in FIGS. 7 and 8, a gap (t4) of approximately 0.4˜0.8 mm may beformed between an inner circumferential surface of the stator laminator25 and an outer circumferential surface of the rotor laminator 27 so asto improve efficiency of the motor 22.

The steel plate constituting the stator laminator 25 of the drivingmotor 20 or the rotor laminator 27 may have a thickness of less than1/100 of the total heights of the stator and rotor, respectively. Therotor laminator 27 is formed so that its height (H3) may be 3˜7 times ofa wrap height (H4) of a fixed scroll 31 and an orbiting scroll 32.

The upper and lower end plates 28A and 28B are respectively formed tohave a thickness (t5) of approximately 1˜4 mm. A balance weight 29eccentric at a certain angle in a circumferential direction is formed onthe upper end plate 28A either integrally, or at a later point infabrication. A thickness (t6) of the balance weight 29 may be less thantwo times the thickness (t5) of the upper end plate 28A so as to enhancereliability of the motor 20.

The upper and lower end plates 28A and 28B may either completely orpartially cover the magnetic flux barriers 27 a of the rotor 22 so as toform a path through the rotor 22 in the upper and lower directions.

The rotation shaft 23 may have a substantially circular cross-section soas to fit into the shaft hole of the rotor 22. An oil hole 23 apenetrates the length of the shaft 23. An oil feeder 23 b, which may beimplemented as a Trochoid pump, is disposed at the lowest end of the oilhole 23 a for drawing oil in from the casing 10.

The rotation shaft 23 may be coupled to the shaft hole of the rotor 22by numerous methods including, for example shrinkage fit of an outerdiameter or shrinkage fit of an inner diameter. Deformation of the outercircumferential surface of the rotor 22, which in some instances isrelatively weak, can be minimized by shrinkage fit of an inner diameter.

The rotation shaft 23 is formed so that its length may be 2˜6 times of aheight of the rotor laminator 27, and so that its diameter (D4) may be1/6˜¼ times a diameter (D5) of a plate portion of a fixed scroll 31.

In this embodiment, the compression part 30 includes a fixed scroll 31fixed on an upper surface of a main frame 1 and an orbiting scroll 32orbitably disposed on an upper surface of the main frame 1 so as to forma plurality of compression chambers P by being engaged with the fixedscroll 31. An Oldham's ring 33 is disposed between the orbiting scroll32 and the main frame 1, for orbiting the orbiting scroll 32 andpreventing a rotation of the orbiting scroll 32. A high/low pressureseparating plate 34 is installed at a rear surface of the plate portionof the fixed scroll 31, for dividing the inside of the casing 10 into ahigh pressure portion and a low pressure portion. A backflow preventingvalve 35 acts to prevent backflow of discharge gas by opening andclosing a discharge port 31 c of the fixed scroll 31.

The fixed scroll 31 includes a fixed wrap 31, which is an involutelyformed at a lower surface of the plate portion and which constitutes onepair of compression chambers P. An inlet 31 b is formed at a sidesurface of the plate portion and is connected to the suction pipe SP. Adischarge port 31 c formed at the center of an upper surface of theplate portion and is connected to the center of the fixed wrap 31 a, fordischarging compressed gas the upper portion of the casing 10.

The orbiting scroll 32 includes an orbiting wrap 32, which is aninvolutely formed on an upper surface of the plate portion, and whichconstitutes one pair of compression chambers P together with the fixedwrap 31 a. A boss portion 32 b is formed at the center of a lowersurface of the plate portion for receiving a driving force of thedriving motor 20 by being coupled to the rotation shaft 23. A backpressure chamber 1 a is formed on an upper surface of the main frame 1and supports the orbiting scroll 32 and contains oil therein. The backpressure chamber 1 a is formed at a position where its outer diameterP6) is smaller than an outer diameter P2) of the rotor of the drivingmotor 20 so as to stabilize the operation of the orbiting scroll 32.

The fixed scroll 31 and the orbiting scroll 32 are formed by a castingmethod. Either the fixed scroll 31 and/or the orbiting scroll 32 may besolid-lubrication processed using a solid lubricant such as MoS2 and Lubso as to reduce a frictional loss. The orbiting scroll 32 may be formedof a material having a weight less than that of the fixed scroll 31 soas to improve efficiency of the driving motor 20.

Oil having acceptable mixture characteristics with a given refrigerantmay be used, thereby preventing a ‘double-separation’ phenomenon inwhich the refrigerant and the oil are separated from each other at asliding or friction portion of the compression part 30. Accordingly,frictional losses and abrasion of the compression part 30 can bereduced.

When a hydro-fluorocarbon (HFC) based-refrigerant is used, fatty-acidester oil is used for lubrication. Also, when a hydro-chlorofluorocarbon(HCFC)-based refrigerant is used, fatty-acid mineral oil is used forlubrication. The fatty-acid ester oil typically has a viscosity of 2˜70cSt at a temperature of 40° C., and a viscosity of 1˜9 cSt at atemperature of 100° C., and is ester-coupled in a molecule at least twotimes. The fatty-acid mineral oil typically has a viscosity of 32˜68 cStat a temperature of 40° C. and is ester-coupled in a molecule at leasttwo times.

In order to ensure a continuous supply of oil to the compression part30, oil is filled in the casing 10 to a height lower than a lowest endof the stator 21. Further, by minimizing the length of the rotor, and bysizing the various components and gaps therebetween as discussed above,interference between the stator 21 and the rotor 22 due to an eccentricload on the rotation shaft 23 can be prevented.

A bearing 2 supporting a lower end of the rotating shaft 23 is mountedon the bottom of the casing 10. When power is supplied to the drivingmotor 20, and the rotation shaft 23 rotates together with the rotor 22,the orbiting scroll 32 moves in an orbital fashion on an upper surfaceof the main frame 1, as guided by the Oldham ring 33. One pair ofcompression chambers P are consecutively moved between the orbiting wrap32 a of the orbiting scroll 32 and the fixed wrap 31 a of the fixedscroll 31. As the orbiting scroll 32 continuously orbits, thecompression chambers P have a decreased volume, thereby sucking,compressing, and discharging refrigerant gas.

In certain embodiments, the driving motor 20 is a synchronous reluctancemotor which generates a rotation force by being synchronously rotated bya reluctance torque in a direction such that magnetic resistance isminimized. Accordingly, slippage between the stator 21 and the rotor 22may be greatly reduced. Additionally, when an induction current flowsinto the rotor 22, thermal loss from the rotor 22 may be reduced toenhance efficiency of the motor 20.

In order to ensure that contraction of the stator laminator 25 in theradius direction is uniform, if the stator 21 is shrinkage fit into thecasing 10, the stator laminator 25 may be symmetrically formed, and awidth of the stator laminator 25 and a length of the protruding fixingportion 25 c may be sized to maintain a certain strength. Accordingly,the rotor insertion hole 25 b of the stator laminator 25 maintains asubstantially circular shape, and an air gap between the stator 21 andthe rotor 22 is uniformly maintained. This prevents interference betweenthe rotor 22 and the stator 21, and enhances reliability of the drivingmotor 20 and the compressor.

The coil 26 may be implemented by forming an enamel coating layer on anouter circumferential surface of a copper wire, thereby preventing avoltage loss due to hydrolysis, cracking, softening, expansion, and/orbreakdown. Also, an insulation film formed of a crystalline plastic filmmay be interposed between the coil 26 and an inner circumferentialsurface of the protruding poles 25 a of the stator 21, therebypreventing any lowering in strength, tensile characteristics, orelectrical insulating characteristics and enhancing reliability of thedriving motor 20.

As discussed above, in certain embodiments, the rotor laminator 27 iscomprised of a plurality of steel plates. In some embodiments, the steelplates are formed such that a distance (t1) from ends of the magneticflux barriers 27 a to an outer circumferential surface of the steelplate is substantially the same for all of the magnetic flux barriers.Further, a width (t2) of the magnetic flux barriers 27 a in the radiusdirection, and a separation distance (t3) between adjacent magnetic fluxbarriers 27 a in the radius direction increases towards the center. Thishelps to minimize deformation of the steel plate when the rotation shaft23 is shrinkage fit into the rotor laminator 27.

In the aforementioned embodiment shown in FIG. 4, the distance (t1) fromthe ends of the magnetic flux barriers 27 a to an outer circumferentialsurface of the steel plate was uniform for all of the magnetic fluxbarriers. However, in the embodiment shown in FIG. 5, the distance (t1)from each end of the magnetic flux barriers 27 a to an outercircumferential surface of the steel plate varies for different ones ofthe magnetic flux barriers. The distance t1 from the end of the longestflux barriers to the outer circumferential surface of the steel plate isgreater than the distance t1 for the shortest flux barriers.

In yet another alternate embodiment, as shown in FIG. 6, a bridge 27 bfor connecting an inner surface and an outer surface of some of themagnetic flux barriers 27 a is provided. In this embodiment, thedistance (t1) between an end of each of the magnetic flux barriers 27 aand an outer circumferential surface of the steel plate can be uniformas shown in FIG. 4, or can be different from each other as shown in FIG.5. Further, although the embodiment shown in FIG. 6 has only theshortest magnetic flux barriers with a bridge 27 b, in other embodimentssome or all of the other magnetic flux barriers may also have a bridge27 b.

When the distance (t1) between an end of each of the magnetic fluxbarriers 27 a and an outer circumferential surface of the steel platevaries as shown in FIG. 5, or when a bridge 27 b is formed at a middleportion of one or more of the magnetic flux barriers 27 a as shown inFIG. 6, the strength of the steel plate is enhanced. This helps toprevent thermal deformation of the steel plate.

When the a compressor in accordance with embodiments as broadlydescribed herein is applied to an air conditioner, a thermal loss due toslippage of the driving motor is decreased, thus enhancing the functionof the compressor and the air conditioner. Furthermore, losses due toemissions are decreased, thus enhancing the function of the compressorand the air conditioner having the same.

Further, when an eco-friendly refrigerant is used, oil easily mixed withthe eco-friendly refrigerant has improved abrasion resistance andlubricating characteristics. Accordingly, reliability, durability andcapacity of the scroll compressor and the air conditioner having thesame is improved.

FIG. 9 shows an air conditioner 100 that incorporates a compressor asshown in FIGS. 1-8. As a result, the air conditioner has all of thebenefits and advantages discussed above.

A compressor having an oil pumping system as embodied and broadlydescribed herein has numerous applications in which compression offluids is required, and in different types of compressors. Suchapplications may include, for example, air conditioning andrefrigeration applications. One such exemplary application is shown inFIG. 9, in which a compressor 910 having an oil pumping assembly asembodied and broadly described herein is installed in arefrigerator/freezer 900. Installation and functionality of a compressorin a refrigerator is discussed in detail in U.S. Pat. Nos. 7,082,776,6,955,064, 7,114,345, 7,055,338 and 6,772,601, the entirety of which areincorporated herein by reference.

Another such exemplary application is shown in FIG. 10, in which acompressor 1010 having an oil pumping assembly as embodied and broadlydescribed herein is installed in an outdoor unit of an air conditioner1000. Installation and functionality of a compressor in an airconditioner is discussed in detail in U.S. Pat. Nos. 7,121,106,6,868,681, 5,775,120, 6,374,492, 6,962,058, 6,951,628 and 5,947,373, theentirety of which are incorporated herein by reference.

Another such exemplary application is shown in FIG. 11, in which acompressor 1110 having an oil pumping assembly as embodied and broadlydescribed herein is installed in a single, integrated air conditioningunit 1100. Installation and functionality of a compressor in such an airconditioner is discussed in detail in U.S. Pat. Nos. 7,032,404,6,412,298, 7,036,331, 6,588,228, 6,182,460 and 5,775,123, the entiretyof which are incorporated herein by reference.

Any reference in this specification to “one embodiment”, “an exemplary”,“example embodiment”, “certain embodiment”, “alternative embodiment”,and the like means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment as broadly described herein. The appearancesof such phrases in various places in the specification are notnecessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to affect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, numerous variations andmodifications are possible in the component parts and/or arrangements.In addition to variations and modifications in the component partsand/or arrangements, alternative uses will also be apparent to thoseskilled in the art.

1. A compressor, comprising: a casing having an inner space to which asuction pipe and a discharge pipe are connected; a compressor deviceinstalled in the casing and configured to compress a fluid receivedthrough the suction pipe and configured to output the compressed fluidthrough the discharge pipe; a driving motor installed in the casing andcoupled to the compression device, wherein the driving motor comprises:a stator comprising a plurality of stator plates laminated together andconfigured to be inserted into an inner circumferential surface of thecasing, each stator plate having a plurality of protruding poles onwhich a coil is wound; a rotor comprising a plurality of rotor plateslaminated together and configured to be rotatably disposed in thestator, wherein each rotor plate comprises a plurality of magnetic fluxbarriers formed therein, and wherein a width of each magnetic fluxbarrier in a radius direction and a separation distance between adjacentmagnetic flux barriers in the radius direction both increase towards thecenter of the driving motor; and a rotation shaft coupled to the centerof the rotor and having one end coupled to the compression device. 2.The compressor of claim 1, wherein each of the stator plates includes arotor insertion hole at the center, and a plurality of protruding fixingportions formed on a peripheral portion of the plate, and wherein aratio of (d1/w1) is greater than or equal to 2.1, wherein d1 is adiameter of the rotor insertion hole, and wherein w1 is a width of thestator plate in the radial direction from an edge of the rotor insertionhole to an outer edge of one of the protruding fixing portions.
 3. Thecompressor of claim 1, wherein each of the stator plates includes aplurality of protruding fixing portions and a plurality of cut-passageswhich alternate with one another along an outer peripheral edge of thestator plate, and wherein the protruding fixing portions couple thestator to an inner surface of the casing.
 4. The compressor of claim 3,wherein an angle θ formed between ends of a protruding fixing portionand a center of the stator is approximately 15°˜35°.
 5. The compressorof claim 3, wherein the cut-passages are formed so that a ratio(QA₀/QA₁) between a sum (QA₀) of a circumferential length of all thecut-passages and a sum (QA1) of a circumferential length of all theprotruding fixing portions is 0.3˜0.7.
 6. The compressor of claim 1,wherein each of the rotor plates is configured such that distances froman outer circumferential surface of the rotor to ends of the magneticflux barriers is substantially uniform for each of the magnetic fluxbarriers.
 7. The compressor of claim 6, wherein each of the rotor platesis configured such that at least one bridge connects an inner surfaceand an outer surface of at least one of the magnetic flux barriers. 8.The compressor of claim 1, wherein each of the rotor plates isconfigured such that distances between ends of the magnetic fluxbarriers and an outer circumferential surface of the rotor are differentfor different ones of the magnetic flux barriers.
 9. The compressor ofclaim 8, wherein each of the rotor plates is configured such that atleast one bridge connects an inner surface and an outer surface of atleast one of the magnetic flux barriers.
 10. The compressor of claim 1,wherein an outer diameter of the stator of the driving motor is largerthan its height in a shaft direction.
 11. The compressor of claim 1,wherein a radius of the stator of the driving motor is smaller than anouter diameter of the rotor.
 12. The compressor of claim 1, whereinupper and lower ends of the rotor of the driving motor are supported byupper and lower end plates, respectively, and wherein each of the endplates has a thickness of approximately 1˜4 mm.
 13. The compressor ofclaim 12, wherein a balance weight, eccentric at a certain angle in acircumferential direction, is integrally formed on at least one of theend plates, and wherein a thickness of the balance weight is less thantwo times the thickness of the end plate to which it is coupled.
 14. Thecompressor of claim 12, wherein either the upper or the lower end platecompletely covers the magnetic flux barriers.
 15. The compressor ofclaim 12, wherein either the upper or the lower end plate partiallycovers the magnetic flux barriers so as to form a path through the rotorin the upper and lower directions.
 16. The compressor of claim 1,wherein at least one of the stator plates is formed of steel and has athickness less than approximately 1/100 of the total height of thestator.
 17. The compressor of claim 1, wherein at least one of the rotorplates is formed of steel and has a thickness less than approximately1/100 of the total height of the rotor.
 18. The compressor of claim 1,wherein the coil wound on the poles of the stator has a height that isapproximately 1.5˜3 times a height of the laminated stator.
 19. Thecompressor of claim 1, further comprising a Trochoid pump configured todraw oil in from the casing, wherein the Trochoid pump is disposed at alower end of the rotation shaft.
 20. The compressor of claim 1, whereinoil is filled in the casing up to a height lower than a lowest end ofthe stator.
 21. The compressor of claim 1, wherein the rotation shafthas a length that is approximately 2˜6 times a height of the drivingmotor.
 22. The compressor of claim 1, wherein the compressor devicecomprises a scroll compressor that includes a fixed scroll formed on alower portion of a plate portion, and an orbiting scroll, wherein theorbiting scroll is coupled to the rotation shaft of the driving motor,and wherein the rotation shaft is formed so that its diameter is ⅙˜¼times a diameter of the plate portion of the fixed scroll.
 23. Thecompressor of claim 1, wherein the compressor device comprises a scrollcompressor that includes a fixed scroll formed on a lower portion of aplate portion, and an orbiting scroll, wherein the orbiting scroll iscoupled to the rotation shaft of the driving motor, and wherein therotor of the driving motor is formed so that a height of the laminatedrotor plates is 3˜7 times of a wrap height of the fixed scroll and theorbiting scroll.
 24. The compressor of claim 1, wherein the compressordevice comprises a scroll compressor that includes a fixed scroll formedon a lower portion of a plate portion, and an orbiting scroll, whereinthe orbiting scroll is coupled to the rotation shaft of the drivingmotor, and wherein the stator is formed so that its outer diameter islarger than an outer diameter of the outermost compression chamberbetween the fixed scroll and the orbiting scroll.
 25. The compressor ofclaim 24, wherein a stepped portion is formed between the driving motorand the compression device.
 26. The compressor of claim 1, wherein a gapof 0.4˜0.8 mm is formed between the stator and the rotor of the drivingmotor.
 27. The compressor of claim 1, wherein the compressor devicecomprises a scroll compressor that includes a fixed scroll formed on alower portion of a plate portion, and an orbiting scroll, wherein theorbiting scroll is coupled to the rotation shaft of the driving motor,wherein the fixed scroll and the orbiting scroll are formed by a castingmethod, and wherein either the fixed scroll or the orbiting scroll issolid-lubrication processed.
 28. The compressor of claim 1, wherein thecompressor device comprises a scroll compressor that includes a fixedscroll formed on a lower portion of a plate portion, and an orbitingscroll, wherein the orbiting scroll is coupled to the rotation shaft ofthe driving motor, and wherein the orbiting scroll is formed of amaterial having a weight less than that of the fixed scroll.
 29. Thecompressor of claim 1, wherein the compressor device comprises a scrollcompressor that includes a fixed scroll formed on a lower portion of aplate portion, and an orbiting scroll, wherein the orbiting scroll iscoupled to the rotation shaft of the driving motor, and wherein a backpressure chamber for supporting the orbiting scroll by containing oiltherein is formed on an upper surface of a main frame located under alower surface of the orbiting scroll.
 30. The compressor of claim 1,wherein a height difference between a center of the rotor and a centerof the stator is within the range of approximately 2˜3 mm.
 31. Thecompressor of claim 1, wherein the rotation shaft is coupled to therotor by a shrinkage fit.
 32. The compressor of claim 1, wherein thedriving motor is synchronously rotated by a reluctance torque in adirection such that magnetic resistance is minimized.
 33. The compressorof claim 1, wherein when a hydro-fluorocarbon (HFC) based-refrigerant isused, fatty-acid ester oil is used for lubrication, and when ahydro-chlorofluorocarbon (HCFC)-based refrigerant is used, fatty-acidmineral oil is used for lubrication.
 34. The scroll compressor of claim33, wherein the fatty-acid ester oil has a viscosity of 2˜70 cSt at atemperature of 40° C. and a viscosity of 1˜9 cSt at a temperature of100° C. and is ester-coupled in a molecule at least two times, and thefatty-acid mineral oil has a viscosity of 32˜68 cSt at a temperature of40° C. and is ester-coupled in a molecule at least two times.
 35. Thecompressor of claim 1, wherein the magnetic flux barriers are formed topenetrate the rotor in a shaft direction.
 36. The compressor of claim 1,wherein an insulation film formed of a crystalline plastic film having aseparation transition temperature of more than approximately 50° C. isinterposed between the coil and the stator.
 37. The compressor of claim1, wherein the coil comprises an enamel coating layer having aseparation transition temperature greater than approximately 120° C. 38.The compressor of claim 3, wherein each of the protruding fixingportions and each of the cut-passages are respectively formed so as tohave the same shape and area with the same interval.
 39. An airconditioner comprising the compressor of claim
 1. 40. A compressor,comprising: a casing having an inner space to which a suction pipe and adischarge pipe are connected; a compressor device installed in thecasing; a driving motor installed in the casing and coupled to thecompressor device, wherein the driving motor comprises: a statorcomprising a plurality of stator plates laminated together andconfigured to be inserted into an inner circumferential surface of thecasing, each stator plate having a plurality of protruding poles onwhich a coil is wound; a rotor comprising a plurality of rotor plateslaminated together and configured to be rotatably disposed in thestator, wherein each rotor plate comprises a plurality of magnetic fluxbarriers formed therein, wherein at least one bridge connects an innersurface and an outer surface of at least one of the magnetic fluxbarriers; and a rotation shaft coupled to the center of the rotor andhaving one end coupled to the compression device.
 41. The compressor ofclaim 40, wherein a width of each magnetic flux barrier in a radiusdirection and a separation distance between adjacent magnetic fluxbarriers in the radius direction each increase towards the center of thedriving motor.
 42. A compressor, comprising: a casing having an innerspace to which a suction pipe and a discharge pipe are connected; acompressor device installed in the casing; a driving motor installed inthe casing and coupled to the compressor device, wherein the drivingmotor comprises: a stator comprising a plurality of stator plateslaminated together and configured to be inserted into an innercircumferential surface of the casing, each stator plate having aplurality of protruding poles on which a coil is wound; a rotorcomprising a plurality of rotor plates laminated together and configuredto be rotatably disposed in the stator, wherein each rotor platecomprises a plurality of magnetic flux barriers formed therein, andwherein distances between ends of the magnetic flux barriers and anouter circumferential surface of the rotor plate are different fordifferent ones of the magnetic flux barriers; and a rotation shaftcoupled to the center of the rotor by shrinkage fit and having one endcoupled to the compression device.
 43. The compressor of claim 42,wherein a width of each magnetic flux barrier in a radius direction anda width between adjacent magnetic flux barriers in the radius directioneach increase towards the center of the driving motor.
 44. Thecompressor of claim 43, wherein at least one bridge connects an innersurface and an outer surface of at least one of the magnetic fluxbarriers.
 45. The compressor of claim 42, wherein at least one bridgeconnects an inner surface and an outer surface of at least one of themagnetic flux barriers.